This question refers to Section 307 of the IPC (Attempt to murder). The section provides different punishments based on the circumstances.
The general punishment for attempt to murder is imprisonment up to 10 years and a fine.
If hurt is caused, the punishment can be enhanced to imprisonment for life or the punishment mentioned above.
The second paragraph of S.307 contains a special, harsher provision: if a person already under a sentence of life imprisonment commits this offence and causes hurt, they may be punished with death.
The question is poorly phrased ("A imprisonment, if...") but likely refers to the range of punishments available under the section. Since the court has the discretion to award imprisonment for a term, life imprisonment, or death (in the specific case of a life convict), "All of the above" represents the possible outcomes.